Abrading device



March 4, 1941. J. L. CULPEPPER 2,234,109

ABRADING DEVICE 7 Filed Aug. 22, 1940 2 Sheets-Sheet 1 Jams 1 val 2011 Patented Mar. 4, 1941 UNITED STATES PATENT OFFICE annanmo nsvroa James Luther comm, Pearl Harbor, Territory of Hawaii Application. sum 22, 1940, Serial No. 353,124

3Ciaims- This invention relates to a novel abrading device and more particularly to a sanding machine adapted to be used as an attachment to a drill press.

More particularly it is an aim of the invention to provide an abrading device including a pluraiity of abrading disks mounted to turn freely relatively to a rotatable cross head and adapted to be rotated by frictional engagement with the surface to be treated in a direction opposite to the rotation of the cross head for uniformly scraping the surface to be treated.

In abrading devices employing a driven rotary abrading disk, a portion of the surface adjacent the axis of the disk is not scraped as much as the portion adiacent the periphery and as a result it is difllcuit to secure a uniformly abraded surface. In the present invention, the planetary action resulting from the rotation of the disks around a stock or shaft and the rotation of the individual disks relatively to the cross head re suits in a substantially uniform treatment of the surface being scraped.

Still anotherpim of the invention is to provide a means whereby abrading members may be individually adjusted relatively to the cross head for adjustabiy positioning them relatively to one illustrate a preferred embodiment thereof, and

wherein:

Figure l is a top plan view of the abrading device,

Figure 2 is a side elevationai view of the same, Figure 3 is a longitudinal vertical sectional view taken substantially along the plane of the line.

Figure 4 is a transverse vertical sectional view taken substantially along the 4-4 of Figure 1,

plane of the line Figure 2,

partly in section, showing a slightly modified form of theinvention, and

' Figure 'l is a perspective view of the abrading element shown detached from the device.

Referring more parti cularly .to the drawings,

wherein like reference characters designate like or corresponding parts throughout the different views. ill designates generally the abradlng or sanding machine including a stock or shaft H which is adapted to be secured at its upper end. 5 in the chuck of a drill press, not shown, in a conventional manner. The stock Ii is provided with a restricted opposite end I2 in the upper portion of which is mounted a collar i3. The free end of the restricted portion I2 is secured w in one end of a universal Joint it in any suitable manner, not shown, which end serves to retain thecoliar IS in position on the stock H, as best illustrated in Figure 3. A cross head I5 is provided with a recess i6, intermediate of its ends, to receive the opposite end I! of the universal joint ll which is detachabiy secured thereto by means of a set screw is. An expansion coil spring is is disposed between the collar i3 and the upper side of the cross head l5. As best seen in Figure 3, the upper coil of the spring i9 engages around the lower portion of the periphery of the collar l3 and against the under side of an annular flange 20 which extends outwardly from theupper portion of the periphery of the collar.

The cross head I, adjacent each of its ends, is provided with a perpendicular bore 2 I, in which is rotatabiy mounted a portion ofthe shank of a headed pin 22. An angular lubricating bore 23 communicates with each of the bores Z I Each of the bores 23 is provided with an internally threaded open end 24, which opens outwardly of the upper side of the cross head ii. The opposite ends of .the bores 23 are sealed at 25. The

bores 23 are adapted to be filled with. a lubricant the bores 28 extend downwardly and outwardly relatively to the end portions of the cross head I so that the lubricant contained therein will be directed toward the bores 21 by centrifugal force when the device is in operation. l

A disk shaped abrading member 21 is v to be connected to each of the pins 22. Each of the abradlng members 21 includes a disk portion 20- which is provided with an upset peripheral flange 2| the ends of which terminate in spaced apart relationship to one another to form a gap ll. The abrading members 21 are each provided with an upset centrally disposed enlargement 3! having an upwardly opening centrally disposed recess 12 for receiving the iower portion of the shank of one of the pins 22. The poradapted it 1 member '35 is shaped and sized to fit over the the abradingmembers 21 may be raised to com- Y pensate for wear on the under side of the heads of the pins 22, on the washers 34, on cross head I5, and on the portions 3! to thereby prevent the disks 2'! from rocking relatively to the cross head l5. Washers or anti-friction members 34 are preferably disposed between the cross head 15 and the headed ends of the pins 22 and the enlargements 3| to prevent wear on the cross head, pins and enlargements.

As best seen in Figure 7, a cup shaped abrading outer side of each of the members TL and is provided with a flange 36 for engaging the outer side of the flange 29. The flange 36 is provided with a gap 31 to register with the gap 30. A spring clip 38 is yieldably disposed around the outer side of the flange 36 of each of the abrading elements 35 and is provided with a hooked end 39 for engaging around corresponding ends of the flanges 23 and, as best seen in Figure 5, and an inturned opposite end for engaging over the opposite ends of the flanges 29 and 36. The spring clip 38 is adapted to resiliently clamp the flange 36 to the outer side of the flange 29 to provide means whereby an abrading element 35 may be detachably mounted on each of the abrading members 27. The terminals in the ends 40 of the clips 38 extend inwardlyto provide handle 1 2'! to revolve around the stock ll.

portions by means of which the clipsm-ay be attached to or detached from the members 21. The outer sides of the disk portions 28 and the flanges 29 are adapted to be serrated or roughened, not shown, for frictionally engaging the inner sides of the abrading elements 35 to prevent said elements from moving relatively to the members 21 when attached thereto by the clips 38. The abrading elements 35 may be provided with a coating of any one of a number of abrading materials, such as sand oremery. As best seen in Figure 3, the outer side of the disk 28, where it 'joins the flange 29, is rounded to prevent element 35 wearing through between its bottom and flange 35.

From the foregoing it will be obvious that when the stock H is attached to the chuck of a drill press and is rotated thereby it will rotate the cross head I 5 to cause the abrading members Assuming that the stock and cross head are turning in a clockwise direction, as illustrated in Figure 1,

I when the abrading elements 35 of the abrading members 21 are brought .into contact with the surface to be treated, not shown, frictional contacttherewith will cause the members ,21 to revolve on,-.the pins 22 in a counter-clockwise direction, or in -the opposite direction to which a they are revolving around the stock ll. As a result, the portion of the surface being treated which is-substantially beneath the stock ll will be scraped by the members 21 turning relatively to said portion. inthe direction opposite to the direction in which the cross head is revolving while the remote portions of the members 2.! will surrounding the universal joint.

tion of the disk.

revolve to a certain extent by contact with the outer portion of the part of the surface being treated so that said portion cannot be scraped as much by each individual part of the disk to thereby substantially equalize the scraping or polishing of the surface. In other words, the portions of the abrading members which are disposed between the pins 22 will be turning against the surface being treated while the portions beyond the pins will be turning with the surface. The expansion coil spring [9 permits the cross head to rock relatively to the stock H on its universal joint 14 so that the abrading members 21 may adjust. themselves to portions of the S111? face which are not level and also prevents the cross head I5 from rocking sufllciently so that the abrading elements 35 will be moved out of contact with the surface which would occur if the cross head is moved from its normal position through an arc in excess of degrees. For some operations, such as paralleling wood, it is necessary that the cross head I 5 be rigidly disposed relatively to the stock or shaft ll. When the device I9 is used for such work, a rigid sleeve 4| replaces the spring IQ for holding the cross head 25 I5 rigid relatively to the stock ll. -These parts. may be interchanged readily by merely loosening the set screw l8 and detach the cross head l5.

Various modifications and changes are contemplated and may obviously be resorted to as only a preferred embodiment of the invention has been disclosed.

I claimas my invention: 1. A surfacing device comprising a stock adapted to be connected to the chuck of a drill press to be rotated thereby, a cross head, a universal joint connecting said cross head and stock, abrading members disposesd beneath and rotatably connected to the cross head for engaging a surface to be treated, a collar on the stock above the 40 universal joint, and an expansion coil spring mounted between the collar and crosshead and 2. An abrading machine comprising a rotating shaft, a cross head secured to one end of said 45 shaft, abrading members connected to said cross head and having their working surfaces disposed substantially in the same plane for engaging the surface to be treated, said abrading members being mounted to rotate freely relatively to the cross head whereby said members will be rotated in opposite directions to the cross head and shaft through frictional engagement with the surface to be treated, a universal joint for connecting the crosshead, intermediate of its ends, to said shaft. and yieldable means for nor-i mally retaining the crosshead substantially at a right angle to the shaft, and for limiting its rocking movement relatively to the shaft, said yieldable means including a collar secured to the 6 I head and surrounding the universal joint.

3. In a surfacing device, an abrading member comprising a disk having an upset peripheral flange, said flange being provided with a gap, an abrading element constructed and arranged to receive said disk, and a spring clip having end portionsdetachably connected to the ends of the flange, formed by the gap, said clip engaging around the flange portion of the abrading member for yieldably clamping it to the flange por- JAMES L; CULPEPPER. 

